WO 2010/015959 (A2) discloses an X-ray photon detector for an imaging device comprising a cathode, a converter material and a substrate. The cathode comprises an outwardly extending plate and a base plate. The converter material is attached to a side of the outwardly extending plate. The substrate comprises an anode and is attached to the converter material.
WO 2013/088352 A2 discloses a radiation detector having an anode and a cathode segmented into anode and cathode segments, respectively. Herein the anode segments are provided with mutually different electrical potentials. A similar approach is adopted for the cathode segments.
U.S. Pat. No. 5,111,052 discloses a radiation sensor having a semiconductor substrate provide with a common electrode and a split electrode disposed on one and same surface of said substrate.
X-ray detection for X-ray imaging can be made with such semi-conductor X-ray detector arranged perpendicular or non-perpendicular inclined to the X-ray radiation. The inclined or edge-on detection has several benefits over perpendicular or face-on detection, among them an improved detective quantum efficiency for materials with lower atomic numbers, as e.g. silicon.
However, in case of an inclined detection and in particular when using lower atomic number detector materials, X-ray radiation entering into the X-ray detector is potentially shared over several detector electrodes leading to a spatial image resolution loss.
In detail, in case of an inclined detection, a direction of an electric field between a detector cathode and a detector anode makes an angle with respect to the direction of the incoming X-ray radiation, which is equal to an inclination angle of the incoming X-ray radiation with respect to the surface normal of the X-ray detector. A charge transported between the detector cathode and the detector anode can then be collected by either one of e.g. two adjacent detector anodes. Hence, the charge may be wrongly allocated with respect to a lateral position of an actual interaction site, which may lead to a degrading lateral image resolution and therefore to a spatial image resolution loss.